1. Technical Field
The present invention relates to illuminating devices, and particularly, to a street illuminating device with a number of solid state light emitting elements.
2. Description of Related Art
Solid state light emitting elements, such as light emitting diodes (LEDs) have been widely used in street illuminating devices.
An LED is capable of producing a visible light in a certain wavelength. However, 80% to 90% energy of the LED is converted to heat, which needs to be dissipated, and only the small remainder is converted to the light.
The light from an LED needs to be gathered if a higher light concentration and brightness are needed. However, if a number of LEDs are used, it becomes complicated to efficiently gather light for each LED.
What is needed, therefore, is a street illuminating device with a number of solid state light emitting elements, which is compact, and in which light gather and heat dissipation are simply accomplished.